The secondary action button needs to be a different color and have a left margin to separate it from its sibling. We can use the following rule to reference btn, then target its immediate sibling with the same class:

.btn {
...
& + & {
margin-left: 15px;
background: firebrick;
}
}

If two btn classes are adjacent siblings, the second one will get the firebrick background and left margin. Here’s the CSS output:

As we just learned, the “double ampersand” sibling selector is a handy solution that keeps us from writing extra CSS and classes in our markup. Methods like these are some of the many ways Sass helps us write cleaner, more efficient front-end code.

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